Process for manufacturing driers



Patented Aug. 30, 1938 UNITED STATES PATENT OFFICE PROCESS FORMANUFACTURING DRIERS Netherlands No Drawing. Application October 15,1935, Se-

rial No. 45,146. In Germany October 27, 1934 4 Claims.

It is well known that driers are manufactured by heating fatty acid,resinie acid, naphthenic acid or vegetable oil with suitable metalcompounds whereby the corresponding metal soaps 5 are formed.

Usually linolic acid is the fatty acid used. In place thereof it hasalready been proposed to use the fatty acids of wood oil and of latealso the acids derived from castor oil have been suggested.

The known processes utilizing the acids from castor oil or the glycerolester of the acid, are used for the manufacture of driers with a highcontent of metal and, as a matter of fact, about twice the quantity ofmetal has been used or taken up by the castor oil, as compared withother prior known processes.

There is, for example, a known cobalt drier which is manufactured fromcastor oil fatty acids. and has a cobalt content of at least about 15%.

These driers obtained from castor oil acids are relatively difficultlysoluble in oil, turpentine or turpentine substitute. In order todissolve them in oil, the latter must be heated to about 200 C.

Cobalt linoleate with a content of 6% cobalt is pasty. In order todissolve it in linseed oil, temperatures of 150 C. must be applied.Products with still higher cobalt content require correspondingly highertemperatures to effect solution.

It hasbeen found that driers may be manufactured which have a normalmetal content and which may be dissolved in linseed oil even attemperatures of 100 C. and which are soluble in turpentine or in asubstitution product of turpentine at an ordinary temperature. Theexpression .normal metal content means that amount or content of metalin the finished drier which replaces exactly the hydroxyl hydrogen ofthe hydroxy fatty acid radical. The method of producing such dryingagents is as follows:

40, Castor oil or other oils containing hydroxy groups are caused toreact with suitable metal compounds or, if desired, with metals whichthemselves enter easily into reaction, and with only so much of thelatter that one hydrogen atom 45 in each fatty acid radical of theglyceride is substituted by metal. 7

In this way a drying agent is obtained which has merely a normal metalcontent, i. e., only the hydroxyl hydrogen of the acid radical isreplaced 50 by metal.

For castor oil and cobalt a product with a maximum content of about 8%of cobalt is obtained, the manganese product has about 5% of manganese,the lead product about 29% of lead.

The temperature at which the oil and the metal compound are allowed toact on each other may not exceed 250 C. and the metal may not be appliedin excess in view of the circumstance referred to above, since otherwisethe final products are not soluble at a low temperature.

The following examples illustrate the manner in which the invention maybe carried into effect:

Example 1.Castor oil is heated to 200 C. and so much of a suitablecobalt compound is added that the final product contains 7% of cobalt.Subsequently the mixture is heated further with stirring until solutionis achieved, the temperature being at 220 C. A paste of a brown-redcolour is obtained which dissolves in oil at 100 C.

Example 2.In the same way as in Example 1, castor oil is heated with somuch litharge that the final product contains 29% of lead. It is ofimportance to see that the temperature does not exceed 220 C. in orderto avoid saponification of the castor oil.

By the expression metals ordinarily employed in the production of driersand similar expressions, I have referenceto cobalt, manganese and lead.

I claim:

1. A drier for paints, varnishes and the like comprising a castor oilmetal compound in which substantially only the hydroxyl hydrogen of theacid radical is replaced by a drier metal, which drier may be dissolvedin linseed oil at 100 C.

2. A drier for paints, varnishes and the like comprising a castor oilmetal compound in which substantially only the hydroxyl hydrogen of theacid radical is replaced by a drier metal.

3. Process for the manufacture of driers from castor oil which consistsin heating said castor oil with one of the class consisting of metalsand compounds of metals ordinarily employed in the production of driersin such proportions that substantially onlyrthe hydroxyl hydrogen of thefatty acid radical is replaced by a drier metal.

4. Process for the manufacture of driers in which castor oil issubjected to the action of one of the class consisting of metals andcompounds of metal ordinarily employed in the production of driers at atemperature not exceeding 250 0., the metal or metal compound beingemployed in such proportion that in the resulting drier substantiallyonly the hydroxyl hydrogen of the fatty acid radical is substituted by adrier metal.

REMMET PRIES'I'ER.

